Gas tank tap with integrated pressure reducer, equipped with a safety valve

Description

[0001] The invention relates to an integrated regulator valve (RDI) equipped with a safety valve that activates in case of overpressure, usable on a pressurized gas container, such as a medical oxygen cylinder.

[0002] Typically, in an integrated regulator valve (IRV) intended to equip a pressurized gas container, such as a gas cylinder, the so-called "low pressure" release is obtained by means of a piston and a regulating spring, which allows the adjustment of the release pressure.

[0003] Low-pressure expansion allows the gas to be decompressed, meaning its pressure is reduced, from the so-called "high" pressure—the pressure the gas has when compressed in the container—to a so-called "low" pressure—the operating pressure lower than the high pressure. For example, the high pressure might be 250 to 300 bar absolute (for a full container), while the low pressure—the pressure after expansion—is generally chosen to be less than 10 bar absolute.

[0004] In such a classic RDI, these regulating pistons and springs, used for gas expansion, are also used to fulfill a safety valve function to evacuate any possible or accidental overpressure after expansion, that is to say any low pressure greater than the desired threshold value.

[0005] Examples of valves with integrated regulator are given by EP-A-2770240 and WO-A-2017 / 194429.

[0006] Using the same piston and regulating spring means that the valve opening pressure is dependent on the expansion pressure, which itself depends on the preload setting of the regulating spring.

[0007] However, this is not ideal because, on the one hand, the valve opening pressure is not easily reproducible from one tap to another and, on the other hand, a failure of the piston and / or the regulating spring would result in the loss of two main functions, namely the regulation of the gas and the release of overpressure, and not just one, namely that of regulation.

[0008] More generally, modifying the architecture of a valve with integrated regulator or RDI is not easy due to existing space and compactness constraints.

[0009] Furthermore, US-A-2212626 is known to offer a standalone assembly consisting of a gas regulator equipped with a safety valve, designed to connect to a gas line carrying high-pressure gas. The high-pressure gas from the gas line enters and flows through a channel containing a movable pressure-regulating element that reduces its pressure, before entering a service chamber supplied with the reduced gas. The service chamber houses the valve and the pressure-regulating means that act on the movable element. In the event of overpressure, the excessively pressurized gas is released through the exhaust ports of the safety valve, whereas under normal operating conditions, i.e., in the absence of overpressure, the reduced gas exits the service chamber through a gas outlet port in the wall of the service chamber.Such an assembly can be easily coupled to an independent gas line but not to an RDI due to a different architecture and gas flow within RDIs.

[0010] The problem is therefore to propose a valve with integrated regulator or improved RDI that avoids the aforementioned disadvantages related to piston and spring, in particular to be able to have a constant valve opening pressure that does not depend on the expansion pressure, and this without causing an increase in the size or overall bulk of the RDI.

[0011] The solution involves a valve with an integrated regulator (RDI), particularly for pressurized gas containers, such as a pressurized gas cylinder, comprising a valve body including: gas pressure-reducing means arranged on the gas circuit to effect a reduction in the pressure of the pressurized gas, i.e., a pressure-reducing of the pressurized gas circulating in the gas circuit and to obtain a relaxed gas, and a gas circuit for conveying a pressurized gas comprising a pressurized gas inlet orifice and a relaxed gas outlet orifice fluidly connected to each other by the internal gas circuit such that the pressurized gas enters the internal gas circuit through the gas inlet orifice and exits through the gas outlet orifice, after having been relaxed by gas pressure-reducing means, said gas pressure-reducing means being arranged on the gas circuit to effect a reduction in the pressure of the pressurized gas (i.e.an expansion valve) circulating in the gas circuit to obtain the expanded gas, and a safety valve to vent excess gas pressure to the atmosphere when the pressure of the expanded gas exceeds a predetermined threshold pressure.

[0012] Furthermore, according to the invention: The gas expansion means include a cylindrical expansion spring acting on a movable expansion piston, the movable expansion piston includes a front part cooperating with a valve stem arranged movable in a connecting conduit fluidly connected to the internal gas circuit, the valve stem carries an expansion valve, said expansion valve cooperating with a valve seat, and the expansion spring is arranged to normally push the movable expansion piston towards the valve stem to generate a displacement of the valve stem within the connecting conduit so as to operate an adjustment of the desired expansion pressure.

[0013] Furthermore, in the tap of the invention: The safety valve includes a cylindrical valve spring acting on a movable valve piston; the release spring, release piston, valve spring, and valve piston are arranged coaxially (AA), and the cylindrical valve spring is arranged within the cylindrical release spring.

[0014] Depending on the embodiment considered, the integrated pressure-reducing valve according to the invention may comprise one or more of the following features: The valve guide is arranged between the valve spring and the rebound spring. The valve spring and the rebound spring are made of steel. The valve spring and the rebound spring are helical. The internal diameter of the rebound spring is larger than the external diameter of the valve spring. The valve spring and the rebound spring are independent of each other. The valve spring and the rebound spring have different stiffnesses. The valve spring is arranged inside the valve guide, preferably coaxially in an internal housing of the valve guide. The movable rebound piston includes a front portion forming a front shield that cooperates with the valve stem. The valve stem is movable axially within the connecting channel. The valve stem has an elongated shape. The valve seat is located at the opening of the connecting channel in the RDI body.The valve seat is arranged peripherally at the outlet of the connecting conduit. The valve seat has a shape complementary to that of the pressure relief valve. The pressure relief valve and the valve seat are located within the valve body. The valve stem and the pressure relief valve are formed as a single piece. The front shield of the movable pressure relief piston has a disc shape and includes a central portion that cooperates with a free end of the valve stem. The valve stem cooperates with the valve seat, for example, made of a suitable material such as nylon or a similar material, in order to either ensure fluid sealing, particularly when the valve is closed, or to set a desired pressure relief level. The front shield includes one or more gas passage orifices arranged around the central portion and passing through the disc-shaped portion. The front shield is integral with the pressure relief piston, for example, press-fitted into the pressure relief piston.The movable expansion piston has a tubular shape with axis AA, comprising an internal housing with an internal annular shoulder extending radially within the housing and including a central opening. The expansion spring presses against the annular shoulder of the expansion piston, preferably via the valve guide. The expansion spring normally pushes the movable expansion piston towards the valve stem. A first seal, such as an O-ring, is arranged in a groove formed in the internal wall of the housing in the RDI body. This first seal is designed to provide fluid sealing between the movable expansion piston and the RDI body. The internal annular shoulder of the expansion piston includes, on the side of the expansion spring and the valve guide, an annular recess forming a groove in which a second fluid seal is arranged.The second seal is arranged to provide fluid sealing between the internal annular shoulder of the expansion piston and the valve piston, specifically a skirt of the valve piston. The valve piston is at least partially movable within the valve guide. The valve piston has a disc shape bordered by a skirt projecting axially towards the second seal and bearing against it. The valve piston also has an axial head projecting axially towards the bell housing. The valve spring is arranged around the axial head of the valve piston. The valve guide has a tubular shape with a central passage along axis AA and includes an external annular shoulder extending radially and away from the outer peripheral surface of the valve guide. The expansion spring bears against this external annular shoulder of the valve guide.The expansion spring, expansion piston, valve spring, valve piston, and valve guide are arranged coaxially in a piston / valve housing within the valve body. The piston / valve housing opens to the outside of the valve body; that is, it is located in the outer wall of the valve body so that it is accessible from the outside through a wide opening. An expansion bell is attached to the valve body and forms a cover closing the piston / valve housing within the valve body. The valve spring presses against a blind bottom of the expansion bell. The expansion bell closes the wide opening of the piston / valve housing like a lid. The expansion bell is generally cup-shaped with a blind bottom and is preferably threaded.The blind bottom of the pressure relief valve bell has one or more openings communicating with the outside atmosphere. The piston / valve housing does not have an outlet for gas at the desired pressure relief. Only gas under pressure can exit through the opening(s) in the blind bottom of the safety valve. The valve body has, on its outer surface, a thread arranged around the piston / valve housing containing the pressure relief spring, the pressure relief piston, the valve spring, the valve piston, and the valve guide. The pressure relief valve bell is screwed, via its threaded hole, onto the threads of the valve body. The connecting conduit fluidly links the internal gas circuit to the piston / valve housing. The piston / valve housing has a blind bottom into which the connecting conduit opens. The free end of the valve stem protrudes into the piston / valve housing.The gas circuit includes one or more internal gas passages through the valve body. The pressurized gas inlet port is carried by a threaded expansion of cylindrical or frustoconical shape, allowing the valve body to be screwed into a gas container. The depressurized gas outlet port is carried by a fitting or nozzle configured to allow the direct or indirect fluid connection of a gas-using apparatus or device, typically via a flexible conduit that carries the gas from the valve to the apparatus or device, preferably a medical apparatus or device. The gas depressurized by the gas depressurization means has a pressure lower than the pressure of the gas under pressure before depressurization, i.e., undepressurized. The pressure of the depressurized gas exiting through the gas outlet port is lower than the pressure of the gas under pressure entering through the gas inlet port.The pressurized gas has an initial pressure, i.e., before expansion, greater than 10 bar abs, preferably greater than 50 bar abs, preferably greater than 100 bar abs, typically at least 200 bar abs, generally at least 250 bar abs. The expanded gas has a final pressure, i.e., after expansion, less than 10 bar abs, preferably less than 6 bar abs. The expansion spring, expansion piston, valve spring, and valve piston are arranged in a housing in the valve body. The valve body is made of brass.

[0015] The invention further relates to a pressurized gas container comprising an integrated regulator valve according to the invention, in particular a gas cylinder.

[0016] The invention further relates to the use of a pressurized gas container equipped with an RDI according to the invention for storing a gas or gas mixture selected from oxygen, air, N2O / O2, He / O2, NO / nitrogen, typically oxygen.

[0017] The invention will now be better understood through the following detailed description, given by way of illustration but not limitation, with reference to the attached figures, among which: Fig. 1 represents an embodiment of an RDI according to the invention, Fig. 2 illustrates the mounting of an RDI according to the invention on a gas cylinder. Fig. 3 is a cross-sectional diagram of the pressure reducing means and the safety valve of an RDI according to the invention, typically the RDI of Fig. 1 , And Fig. 4 is a cross-sectional diagram of an RDI according to the invention.

[0018] Fig. 1 represents an embodiment of a valve with integrated regulator 1 or RDI used for gas distribution according to the invention, which includes a valve body 2 made of brass, namely a CuZn40Pb2 alloy for example.

[0019] The RDI 1 includes gas pressure-reducing means 10, 11, i.e., pressure-reducing means, enabling the gas under pressure to be reduced, that is, the gas pressure to be lowered from a high pressure value of several tens, or even hundreds, of bar abs, to a low pressure value, i.e., a pressure-reducing level. The pressure-reducing level, i.e., the level after pressure reduction, can be fixed or adjusted by means of the pressure-reducing means, as explained below with reference to the Fig. 3 , for example on the order of a few bars (i.e. < 10 bar abs), for example on the order of 4.5 bar abs.

[0020] The valve body 2 is traversed by an internal gas circuit 33, i.e. one or more passages or conduits, allowing the gas, namely a high-pressure gas and the expanded gas, to be conveyed between a fluid inlet 30 carried by an expansion or threaded end 31, of cylindrical or truncated conical shape, and a fluid outlet 40, i.e. a flow outlet, carried by a first outlet fitting 41.

[0021] The threaded end 31 allows the valve body 2 to be screwed onto a gas container 60, such as a gas cylinder, as illustrated in Fig. 2 containing the gas under pressure, i.e. at high pressure, in its internal volume 61.

[0022] Optionally, the body 2 of the RDI 1 may also include another fluid outlet 50, typically a so-called pressure outlet, carried by another outlet fitting 51, which supplies the unexpanded gas, i.e. at high pressure.

[0023] The gas expansion means 10, 11, also called pressure reduction means, are arranged on the internal gas circuit of the body 2, between the gas inlet 30 of the RDI 1 and the low pressure gas outlet 40, also called flow outlet, carried by the outlet fitting 41, i.e. the flow outlet fitting.

[0024] The outlet fittings 41, 51 are made of a copper alloy, in particular brass, for example, a CuZn39Pb3 type alloy is used. They have generally tubular shapes, i.e. elongated with axial passage for the gas communicating fluidly with the internal fluid circuit of the body 2 and opening at the outlet ports 40, 50. The external peripheral wall of these fittings 41, 51 comprises one or more cylindrical sections.

[0025] Furthermore, the body 2 of the RDI 1 is also equipped with a manometer 70 allowing visualization of the gas pressure in the gas circuit of the body 2, upstream of the expansion means 10, 11, which reflects that in the internal volume 61 of the container 60 of pressurized gas.

[0026] On the Fig. 1 And Fig. 4 , the 70 pressure gauge is of the needle type, whereas on the Fig. 2 The pressure gauge 70 is digital, that is to say it is an electronic device with a digital display 71, implementing one (or more) microprocessor associated with one or more temperature and / or pressure sensors and allowing the determination of gas pressure, or even other quantities, such as gas autonomy or residual gas volume in the container 60, and then displaying them on the digital display 71.

[0027] The valve body 2 also carries a flow control element 42, such as a rotary handwheel, cooperating with flow control means to allow a user to adjust the fluid flow rate delivered by the fluid distribution fitting 41, typically flow rates between 0 and 30 L / min, preferably between 0 and 15 L / min, or even 20 L / min. The flow control means may include, for example, a disc with calibrated orifices of different dimensions, i.e., diameters, which correspond to the different selectable gas flow rates.

[0028] In the modes of embodiment of Fig. 1 And Fig. 2 The flow control element 42 is a user-operated rotary handwheel arranged around and coaxially with the fluid distribution fitting 41. The rotary handwheel has a general crown shape and includes slots that are angularly offset from each other and sized to allow a user to insert their fingers to rotate the handwheel clockwise or counterclockwise to set the desired gas flow rate.

[0029] The valve body 2 may include other components, such as a filling connection (not visible), i.e., an additional connection configured to receive a filling port that connects to it mechanically and fluidly to allow fresh fluid to be introduced into the internal volume 61 of the fluid container 60 when it is empty, for example. This filling connection includes a filling valve that normally prevents fluid from escaping through this connection. The filling connection is in fluidic communication with the internal volume 61 of the container 60 via the internal gas circuit of the valve body 2 and the inlet port 30 carried by the threaded fitting 31.

[0030] The tap body 2 may also include a residual pressure mechanism to guarantee or maintain a minimum positive pressure in the container by preventing its total emptying, i.e. a total withdrawal of the fluid.

[0031] Furthermore, as explained below and illustrated in Fig. 3 , the body 2 of the RDI 1 also includes a safety valve 20, 21 allowing to evacuate any excessive pressure in the gas circuit of the valve body 2, downstream of the pressure-reducing means, i.e. to evacuate to the atmosphere any pressure greater than a safety threshold value, for example in the event of an internal leak of the valve.

[0032] Fig. 2 Diagram shows an RDI 1 according to the invention mounted on a fluid container 60 of the ogive-shaped gas cylinder type, i.e., with a cylindrical container body 61 (with axis AA) comprising a tapered end forming a neck with a threaded opening communicating fluidly with the internal volume 61 of the gas cylinder. The RDI 1 is fixed by screwing, via its threaded end 31, into the threaded opening of the neck.

[0033] The hollow cylindrical body of the container 60 comprises an internal volume 61 for containing the gas under pressure, i.e., at high pressure, typically a compressed medical gas such as oxygen, at a pressure of up to 200 to 300 bar absolute, or even more (when the cylinder is full). The internal volume 61 can have a capacity of 0.5 to 10 L (water equivalent), for example 2 L, 5 L, or 7 L. Its diameter is on the order of 10 to 20 cm, typically on the order of 12 to 16 cm, for example approximately 14 cm.

[0034] The body 2 of the RDI 1 (not visible) is protected here by a protective cover 80 comprising a rigid body 81, made of polymer or metal, defining a protective enclosure in which the valve body 2 of the RDI 1 is positioned and fixed to it or to the neck of the bottle 60 by its base 82.

[0035] The rigid body 81 of the cover 80 also includes a carrying handle 84 mounted above the body 81 and connected to it by support uprights 83 to allow a user to manually lift and carry the cover / RDI / bottle assembly. The carrying handle 84 is located opposite the base 82 with respect to the cover body 81.

[0036] Preferably, a pivoting attachment device 85 (partially visible) is also provided, located opposite the outlet fitting 41. This pivoting attachment device 85 is used to attach the cover / RDI / bottle assembly to a hospital bed rail, stretcher rail, or any other similar support, such as a rod or other. When unfolded by the user, the attachment device 85 can pivot between a folded position and a resting position, in which it is positioned along the cover body 81, as illustrated in Fig. 2 and a deployed or hooked position, in which the hooking device 85 is pivoted and angularly away from the hood body 81 so as to permit its lashing or hooking to a bed rail or the like. Such a pivoting hooking device 85 is described by EP-A-2918893

[0037] The pressurized gas is introduced into the internal volume 61, during the filling of the container 60, via the filling fitting and the internal circuit of the RDI 1 (not visible) and through the neck of the container 60. The extraction of the pressurized gas, during withdrawal, is done in the opposite direction.

[0038] During its use, flexible hoses, made of metal or plastic, or other interfaces or devices can be connected and disconnected to the fitting(s) 41, 51 of the RDI 1. The fittings 41, 51 can be nickel-plated, i.e. covered with a nickel-based coating deposited on the brass forming the fittings 41, 51.

[0039] Fig. 3 is a cross-sectional diagram of the pressure reducing means and the safety valve 20, 21 of an RDI 1 according to the invention and Fig. 4 is a cross-sectional diagram of RDI 1 including the elements of Fig. 3 .

[0040] As mentioned above, the RDI 1 includes gas pressure-reducing means 10, 11, 13, and 34 arranged on the gas circuit passing through the body 2 of the RDI 1. These means serve to reduce the pressure of the pressurized gas, i.e., to depressurize the gas circulating in the gas circuit and obtain a depressurized gas. During this depressurization, the pressurized gas goes from the high pressure (i.e., equivalent to the pressure in the cylinder) to a predetermined low pressure, typically less than 10 bar absolute.

[0041] Furthermore, in order to compensate for any possible overpressure, for example resulting from an internal leak, the RDI 1 also includes a safety valve 20, 21 allowing at least part of the gaseous overpressure to be evacuated to the atmosphere when the pressure of the expanded gas exceeds a pre-set threshold pressure.

[0042] As illustrated in Fig. 3 And Fig. 4 , the gas expansion means 10, 11 include a cylindrical expansion spring 10 acting on a movable expansion piston 11, via the valve guide, a movable valve stem 13 within a connecting passage or conduit 32 which connects fluidly to the internal gas circuit 33, i.e. one or more gas passages, and a valve seat 34 cooperating with the valve stem 13 to control the expansion of the gas within the internal gas circuit 33.

[0043] The valve stem 13 has an elongated shape and is movable in axial translation in the connecting conduit 32, i.e. axially in the connecting conduit 32. The connecting conduit 32 and the valve seat 34 are located in the body 2 of the RDI.

[0044] The valve stem 13 carries a relief valve 35 cooperating with the valve seat 34. Advantageously, the valve seat 34 has a shape complementary to that of the relief valve 35 in order to ensure, as appropriate, a seal between them or, conversely, an effective expansion of the gas.

[0045] The valve seat 34 is located at the outlet of the connecting conduit 32 in the body 2 of the RDI, that is to say peripherally to the outlet 36 of the connecting conduit 32, namely on the side of the internal gas circuit 33.

[0046] The movable expansion piston 11 includes a front part or front shield 12 cooperating with the valve stem 13, namely with its free end 13a.

[0047] When the valve stem 13 is pushed back by the cylindrical release spring 10, the pressure relief valve 35 disengages from the valve seat 34, particularly when the valve is opened by the user, in order to expand the gas and thus release gas, which is distributed through the first outlet fitting 41 carrying the gas outlet 40. Conversely, when the valve 1 is in the closed position, the interaction between the pressure relief valve 35 and the valve seat 34 ensures a fluid seal.

[0048] As seen on the Fig. 3 And Fig. 4 , the movable expansion piston 11 and the safety valve 20, 21 are (at least partially) arranged in a piston / valve housing 3 provided in the body 2 of the RDI 1, in particular in the peripheral wall of the body 2 so that the piston / valve housing 3 is open to the outside, via a wide opening 38, so as to be able to arrange in particular the movable expansion piston 11 and the safety valve 20, 21.

[0049] The conduit 32 fluidly connects the internal gas circuit 33 to the blind bottom 3A of the piston / valve housing 3, that is to say that the conduit 32 opens into the piston / valve housing 3 at the level of an inlet orifice 37 provided in its blind bottom 3A.

[0050] A detent adjustment bell 4 externally closes the piston / valve housing 3 and is screwed to the body 2 of the RDI 1, as explained below. The adjustment bell 4 thus closes the large opening 38 of the piston / valve housing 3 like a lid.

[0051] The gas flows through the internal gas circuit 33 arranged in the body 2 of the RDI 1, entering through the pressurized gas inlet 30 and exiting, after expansion, through the expanded gas outlet 40 carried by the gas outlet fitting 41. The gas expansion is achieved through the interaction between the expansion valve 35 carried by the valve stem 13, and the valve seat 34.

[0052] In other words, the expanded gas exits, under normal operating conditions, through the first outlet fitting 41 on the valve body 2; that is to say, no gas outlet is provided from the piston / valve housing 3 to the outside except in the event of overpressure. Indeed, the gas only exits the piston / valve housing 3 in the event of overpressure, when it is vented to the atmosphere through the safety valve 20, 21 via the ports 5, as explained below.

[0053] The front shield 12 of the movable expansion piston 11 preferably has a disc shape comprising a central part 12a cooperating with a free end 13a of the valve stem 13 and, furthermore, one or more gas passage orifices 12b arranged around the central part 12a.

[0054] The valve stem 13, which is axially movable in the connecting conduit 32, passes through the inlet orifice 37 arranged in the bottom 3A of the piston / valve housing 3 so that the free end 13a of the valve stem 13 protrudes into the piston / valve housing 3 and can cooperate with the front shield 12 of the movable expansion piston 11.

[0055] The front shield 12 is integral with the expansion piston 11; for example, the shield can be press-fitted into the expansion piston 11. The expansion piston 11, together with its front shield 12, exerts force on the free end 13a of the valve stem 13 in the event of a vacuum during the opening of the RDI 1, thus releasing the gas contained in the cylinder and obtaining the expanded gas. The shield 12 and the piston 11 are provided with orifices, openings, or passages 12b and 14, respectively, which allow the gas to flow to the valve piston 21.

[0056] The expansion piston 11 has a generally tubular shape with axis AA, comprising an internal housing 15 with an internal annular shoulder 14 extending radially within the internal housing 15 and comprising a central opening 14a, i.e., forming a passage restriction. The expansion spring 10 presses against the annular shoulder 14 of the expansion piston 11 via a valve guide 16.

[0057] More specifically, the valve guide 16 has a general tubular shape and includes a central passage 19 with axis AA with a wide opening at the first end 16a of the valve guide 16 and with a narrowed opening 18, i.e. a restriction of passage, at the second end 16b of the valve guide 16. The first end 16a of the valve guide 16 further includes an external annular shoulder 17 extending radially and away from the external peripheral surface of the valve guide 16.

[0058] The rebound spring 10 bears against the external annular shoulder 17 of the valve guide 16 to push it against the rebound piston 11, given that the external annular shoulder 17 of the valve guide 16 presses against the internal annular shoulder 14 of the rebound piston 11. The external annular shoulder 17 of the valve guide 16 is therefore sandwiched between the internal annular shoulder 14 of the rebound piston 11 and a free active end 10a of the rebound spring 10.

[0059] As can be seen, the valve guide 16 is arranged coaxially (axis AA) and partially inserted into the internal housing of the expansion piston 11, while the cylindrical expansion spring 10 is arranged around the valve guide 16, that is, between the external peripheral wall of the valve guide 16 and the internal wall of the internal housing 15 of the expansion piston 11. The valve guide 16, the expansion piston 11 and the expansion spring 10 are therefore arranged coaxially with each other.

[0060] The release spring 10 normally pushes the movable release piston 11 towards the valve stem 13, causing the valve stem 13 to move within the conduit 32. This disengages the release valve 35 from the valve seat 34, thus allowing adjustment of the desired release pressure. In other words, the valve stem 13 carrying the release valve 35 and the valve seat 34 arranged in the body 2 of the RDI 1 form a release valve / seat assembly.

[0061] A first sealing joint 8, such as an O-ring, arranged in a groove 6 formed in the internal wall of the piston / valve housing 3 formed in the body 2 of the RDI, ensures a fluidic seal between the movable expansion piston 11 and the body 2 of the RDI 1.

[0062] Furthermore, the internal annular shoulder 14 of the expansion piston 11 includes, on the side of the expansion spring 10 and the valve guide 16, an annular recess 14b forming a groove in which a second fluidic seal 9 is arranged.

[0063] Furthermore, as already mentioned, the detent adjustment bell 4 is screwed onto the body 2 of the RDI 1 via an internal thread. It forms a cover closing the housing 3 of the RDI body 2, in which the detent spring 10, the movable detent piston 11, and the valve guide 16 are arranged, as well as the elements of the safety valve 20, 21, as explained below.

[0064] The trigger adjustment bell 4 has a general cup shape with a blind bottom 4a. The blind bottom 4a pushes back the free passive end 10b of the trigger spring 10, that is to say, in other words, the free passive end 10b of the trigger spring 10 rests on the blind bottom 4a of the trigger adjustment bell 4.

[0065] The blind bottom 4a of the pressure relief adjustment bell 4 is pierced with one or more gas passage orifices 5 communicating with the ambient atmosphere and allowing gas overpressures to be evacuated to the outside.

[0066] In other words, the adjustment bell 4 allows adjustment of the preload of the rebound spring 10 and therefore the rebound pressure. The bell 4 is screwed onto the body 2 of the RDI 1, and the preload adjustment, and thus the rebound pressure, is made by adjusting the screw travel. The bell 4 has holes or orifices 5 for gas passage, which allow gas to escape to the outside in the event of the opening of the safety valve 20, 21.

[0067] In addition, the RDI 1 also includes a safety valve 20, 21 comprising a cylindrical valve spring 20 acting on a movable valve piston 21 which are arranged in the housing 3 of the body 2 of RDI 1.

[0068] More specifically, the rebound spring 10, the rebound piston 11, the valve spring 20 and the valve piston 21 are arranged coaxially with axis AA and the cylindrical valve spring 20 is arranged inside the cylindrical rebound spring 10.

[0069] In fact, the cylindrical valve spring 20 is arranged inside the valve guide 16, which is itself arranged in the cylindrical release spring 10, as can be seen on Fig. 3 And Fig. 4 . The external diameter of the cylindrical valve spring 20 is therefore smaller than the internal diameter of the cylindrical release spring 10.

[0070] Furthermore, the cylindrical valve spring 20 presses on the movable valve piston 21, pushing it normally against the second fluidic seal 9 carried by the internal annular shoulder 14 of the expansion piston 11 to ensure a fluidic seal between them. The stiffness of the valve spring 20 is chosen to correspond to the safety pressure threshold, i.e., the pressure threshold, at which the safety valve 20, 21 opens, releasing excess pressure into the atmosphere.

[0071] The movable valve piston 21 has a disc shape 22 bordered by a skirt 23 projecting axially towards the second sealing gasket 9 and pressing upon it, and also carrying an axial head or expansion 24 projecting axially towards the bell 4. The valve spring 20 is inserted around the axial head 24 of the valve piston 21.

[0072] In the event of gas overpressure exceeding the pushing force of the valve spring 20, the movable valve piston 21 will be pushed towards the bell 4 by being detached from the second sealing gasket 9, which will allow the overpressure gas to pass between the second sealing gasket 9 and the skirt 23 of the valve piston 21, due to the resulting breach of the seal, and to travel successively through the orifice 18 of the valve guide 16 and through the orifice(s) 5 of the expansion adjustment bell 4 and to be thus evacuated to the outside.

[0073] By using an independent valve spring 20 and movable valve piston 21 for the safety valve, integrated coaxially in the elements used for the release, in particular the release spring 10, the release piston 11, the opening pressure of the safety valve 20, 21 is constant and can be adjusted independently of the release pressure since the release pressure and the opening pressure of the safety valve are fixed by the stiffness of two different springs each having their own stiffness, therefore elastic force.

[0074] The valve guide 16 guides the valve piston 21 and takes the force of the valve spring 20. The valve guide 16 is held against the expansion piston 11 and the sealing gasket 9, thanks to the force exerted by the expansion spring 10.

[0075] The valve piston opens the safety valve 20, 21 in case of overpressure. When the force exerted on the valve piston 21 by the pressure release (in the event of a first fault) exceeds the force exerted by the valve spring 20, the safety valve 20, 21 opens. The valve spring 20, mounted in the valve guide 16, exerts a constant force on the valve piston 21, thus ensuring a constant opening pressure of the safety valve 20, 21.

[0076] The valve guide 16 is also provided with orifice(s) 18 which allow the gas to be evacuated to the outside in the event of the opening of the safety valve 20, 21.

[0077] Such a pressurized fluid container 60 equipped with an RDI 1 according to the invention is well suited for use in storing a medical grade gas or gas mixture such as oxygen, air, N2O / O2, He / O2, NO / nitrogen, typically oxygen.

Claims

1. Valve (1) with integrated regulator for a pressurized gas container (60) comprising a valve body (2) comprising: - a gas circuit (33) for conveying a pressurized gas, comprising a pressurized-gas inlet orifice (30) and an expanded-gas outlet orifice (40) that are fluidically connected to one another by the internal gas circuit (33) so that the pressurized gas enters the internal gas circuit (33) through the gas inlet orifice (30) and exits therefrom through the gas outlet orifice (40), after having been expanded by gas expansion means (10, 11, 13, 34, 35), said gas expansion means (10, 11, 13, 34, 35) being arranged on the gas circuit (33) in order to reduce the pressure of the pressurized gas circulating in the gas circuit (33) and to obtain the expanded gas, and - a safety valve (20, 21) for discharging a gaseous overpressure to the atmosphere when the pressure of the expanded gas exceeds a preset threshold pressure, in which valve: - the gas expansion means (10, 11, 13, 34, 35) comprise a cylindrical expansion spring (10) acting on a moveable expansion piston (11), - the moveable expansion piston (11) comprises a front portion (12) that cooperates with a valve stem (13) arranged moveably in a connecting duct (32) that is fluidically connected to the internal gas circuit (33), - the valve stem (13) carries an expansion valve (35), said expansion valve (35) cooperating with a valve seat (34), and - the expansion spring (10) is arranged to normally push the moveable expansion piston (11) back towards the valve stem (13) so as to move the valve stem (13) within the connecting duct (32) to adjust the expansion pressure as required. - characterized in that: the safety valve (20, 21) comprises a cylindrical valve spring (20) acting on a moveable valve piston (21), - -the expansion spring (10), the expansion piston (11), the valve spring (20) and the valve piston (21) are arranged coaxially (AA), and - the cylindrical valve spring (20) is arranged in the cylindrical expansion spring (10).

2. Valve according to Claim 1, characterized in that a valve guide (16) is arranged between the valve spring (20) and the expansion spring (10), said valve spring (20) being arranged inside the valve guide (16).

3. Valve according to Claim 1, characterized in that the moveable expansion piston (11) comprises a front shield (12) cooperating with the valve stem (13), preferably with a free end (13a) of the valve stem (13).

4. Valve according to Claim 1, characterized in that the moveable expansion piston (11) has a tubular shape of axis AA comprising an internal housing (15) comprising an internal annular shoulder (14) extending radially into the internal housing (15) and comprising a central opening (14a).

5. Valve according to Claims 1 and 4, characterized in that the expansion spring (10) bears against the annular shoulder (14) of the expansion piston (11), preferably via the valve guide (16).

6. Valve according to Claim 2, characterized in that the valve piston (21) is at least partially arranged moveably in the valve guide (16).

7. Valve according to Claim 2, characterized in that the valve guide (16) has a tubular shape with a central passage (19) of axis AA and comprises an external annular shoulder (17) extending radially away from the external peripheral surface of the valve guide (16), the expansion spring (10) bearing against said external annular shoulder (17) of the valve guide (16).

8. Valve according to Claim 1, characterized in that the expansion spring (10), the expansion piston (11), the valve spring (20), the valve piston (21) and the valve guide (16) are arranged coaxially in a piston / valve housing (3) formed in the valve body (2) and that opens towards the outside of said valve body (2).

9. Valve according to Claim 8, characterized in that a pressure regulation cap (4) is fastened to the valve body (2) and forms a cover closing the piston / valve housing (3) formed in the valve body (2), the valve spring (20) bearing against a blind bottom (4a) of said pressure regulation cap (4).

10. Valve according to Claim 9, characterized in that the blind bottom (4a) of the pressure regulation cap (4) comprises one or more orifices (5) in communication with the outside atmosphere.

11. Valve according to Claim 1, characterized in that the connecting duct (32) fluidically connects the internal gas circuit (33) to the piston / valve housing (3).

12. Valve according to Claim 1, characterized in that the valve seat (34) is located at the mouth (36) of the connecting duct (32) in the body (2) of the valve.

13. Valve according to Claim 12, characterized in that the valve seat (34) is formed about the periphery of the mouth (36) of the connecting duct (32).

14. Pressurized-gas container (60) comprising a valve (1) with integrated regulator according to one of the preceding claims, in particular a gas cylinder.

15. Use of a pressurized-gas container (60) equipped with an IVR (1) according to Claim 14 for storing a gas or a gaseous mixture selected from oxygen, air, N2O / O2, He / O2, NO / nitrogen, typically oxygen.